Writing instrument



FIG. 1 is a front elevational view of a writing instrument according to the present invention;

FIG. 2 is a left side elevational view thereof, the right side elevational view being a mirror image thereof;

FIG. 3 is a top view thereof;

FIG. 4 is a rear elevational view thereof;

FIG. 5 is a bottom view thereof; and,

FIG. 6 is a view of a writing instrument as in FIG. 1 with the cap removed.

The broken line showings in the Figures are for illustrative, environmental purposes only and form no part of the claimed design. 

The ornamental design for a writing instrument, as shown and described. 